A few good points, however, machines change every year or so...I found a lot of misinformation in this blog. The blog was posted eight years ago...2005. Machines have basics, but there are a lot of machines and features not reviewed.
If I was looking for a machine, I would make a list of features I want take it to the dealer, test the machine with a quilt sandwich, go home and search for the best price on the net, take that price less local tax and ask if they can match it.
If you have never sewed, then I would go the garage sale route...maybe. Don't forget your dealer also has a lot of used machines at reduced prices, plus you know they have put them through their paces before putting them up for sale.